Combating arthropods with novel benzyl esters

ABSTRACT

Benzyl esters of the formula ##STR1## in which n is 1,2,3,4, or 5, 
     R 2  is hydrogen, C 1-4  -alkyl, cyano or ethynyl, 
     R 3  is the radical of a carboxylic acid customary in pyrethroids or pyrethroid-like compounds, and 
     at least one R 1  is fluoroalkoxy or fluoroalkylmercapto, or two together are fluoromethylene- or fluoroethylene-dioxy, and the others, if present, are hydrogen or various radicals, 
     which possess arthropodicidal properties. Various alcohols, amines, aldehydes, halides, and the like, corresponding to the alcohol moieties of the esters are also synthesized.

This is a division of application Ser. No. 288,440, filed July 30, 1981,now U.S. Pat. No. 4,438,275, which is a division of application Ser. No.30,579, filed Apr. 16, 1979, now U.S. Pat. No. 4,310,540.

The present invention relates to and has for its objects the provisionof particular new benzyl esters which possess arthropodical properties,active compositions in the form of mixtures of such compounds with solidand liquid dispersible carrier vehicles, and methods for producing suchcompounds and for using such compounds in a new way especially forcombating pests, e.g. insects and acarids, with other and furtherobjects becoming apparent from a study of the within specification andaccompanying examples.

It also relates to new intermediate products for the preparation ofthese active compounds.

Similar active compounds are already known from French PatentSpecification No. 2,290,415 ##STR2## or are present in the commercialproduct Neopynamin ##STR3## However, these compounds have thedisadvantage of too low an activity, above all when low concentrationsare applied.

1. The present invention now provides, as new compounds, the benzylesters of the general formula ##STR4## in which

n represents 1, 2, 3, 4 or 5, the substituents R¹ being selectedindependently of each other when n is 2 or more,

R¹ represents hydrogen, C₁₋₆ -alkyl, C₁₋₆ -halogenoalkyl with 3-6halogen atoms, C₁₋₆ -alkoxy, C₁₋₆ -halogenoalkoxy with 1-6 halogenatoms, C₁₋₆ -alkylmercapto, C₁₋₆ -halogenoalkylmercapto with 1-6 halogenatoms, halogen, optionally substituted phenyl or optionally substitutedphenoxy, or two adjacent radicals R¹, together with the adjoining carbonatoms, form an optionally substituted fused-on benzene ring or form afused-on oxygen-containing heterocyclic five-membered or six-memberedring which is mono- or polysubstituted by fluorine, provided that, informula I, at least one of the radicals R¹ must represent fluoroalkoxyor fluoroalkylmercapto, or two adjacent radicals, together with theadjoining carbon atoms, form an oxygen-containing heterocyclicfive-membered or six-membered ring which is mono- or polysubstituted byfluorine,

R² represents hydrogen, C₁₋₄ -alkyl, cyano or ethynyl and

R³ represents the radical of a carboxylic acid customary in pyrethroidsor pyrethroid-like compounds.

2. This invention also provides a process for the preparation of abenzyl ester of the formula (I) in which

(a) a carbonyl halide of the general formula

    Hal--CO--R.sup.3                                           (II),

in which

R³ has the meaning stated under 1 (above) and

Hal represents halogen, preferably chlorine, is reacted with a benzylalcohol of the general formula ##STR5## in which R¹, n and R² have themeaning stated under 1 (above), if appropriate in the presence of anacid acceptor and if appropriate in the presence of a solvent, or

(b) a salt of a carboxylic acid, of the general formula

    MO--CO--R.sup.3                                            (IV),

in which

M denotes K or Na and

R³ has the meaning stated under 1 (above), is reacted with a benzylhalide of the general formula ##STR6## in which

R¹, n and R² have the meanings stated under 1 (above) and

Hal denotes chlorine or bromine,

if appropriate in the presence of a solvent and if appropriate in thepresence of a quaternary ammonium salt.

3. The new benzyl alcohols of the general formula ##STR7## in which R¹,R² and n have the meanings stated under 1 (above), have also been found.

4. It has also been found that a benzyl alcohol of the formula (III) in3 (above) is obtained when

(a) an aldehyde of the general formula ##STR8## in which R¹ and n havethe meanings stated under 1 (above), is reduced, in the case where R² inthe benzyl alcohol represents hydrogen, or is reacted with HCN, in thecase where R² in the benzyl alcohol represents CN, or is reacted with aGrignard compound of the formula

    R.sup.2 --Mg--Hal                                          (VII),

in which R² represents C₁₋₄ -alkyl or ethynyl, in the case where R² inthe benzyl alcohol represents C₁₋₄ -alkyl or ethynyl, or

(b) when a benzylamine of the general formula ##STR9## in which R¹ and nhave the meanings stated under 1 (above), is reacted with sodium nitriteor potassium nitrite in the presence of an acid, or

(c) when a benzyl halide of the general formula ##STR10## in which R¹,R², n and Hal have the meanings stated under 2 (above), is saponifiedwith an aqueous base.

5. The new benzyl halides of the general formula ##STR11## in which

R² and n have the meanings stated under 4 (above) and

each R¹ represents, independently of any other, hydrogen, C₁₋₆ -alkyl,C₁₋₆ -halogenoalkyl with 3-6 halogen atoms. C₁₋₆ -alkoxy, C₁₋₆-halogenoalkoxy with 1-6 halogen atoms, C₁₋₆ -alkylmercapto, C₁₋₆-halogenoalkylmercapto with 1-6 halogen atoms, halogen, optionallysubstituted phenyl and optionally substituted phenoxy, or two adjacentradicals R¹, together with the adjoining carbon atoms, form anoptionally substituted fused-on benzene ring or form a fused-onoxygen-containing heterocyclic five-membered or six-membered ring whichis mono- or polysubstituted by fluorine, provided that, in this formula,two adjacent radicals R¹, together with the adjoining carbon atoms, mustform an oxygen-containing heterocyclic five-membered or six-memberedring which is optionally monosubstituted or polysubstituted by fluorine,

have also been found.

6. It has also been found that a benzyl halide of the formula (V) in 5(above) is obtained when a compound of the general formula ##STR12## inwhich R¹, R² and n have the meanings stated under 5 (above), ishalogenated in the side chain in a manner which is in itself known.

7. The new aldehydes of the general formula ##STR13## in which R¹ and nhave the meanings stated under 5 (above), but with the proviso that twoadjacent radicals R¹, together with the adjoining carbon atoms, mustform an oxygen-containing six-membered ring which is monosubstituted orpolysubstituted by fluorine, have also been found.

8. It has also been found that an aldehyde of the formula (VI) in 7(above) is obtained when, in compounds of the general formula ##STR14##in which R¹ and n have the meanings stated under 8 (above), the CH₃group is halogenated to the --CH--Hal₂ group in a manner which is initself known and this group is then saponified in the customary mannerto give the aldehyde of the formula (VI).

9. The new benzylamines of the general formula ##STR15## in which R¹ andn have the meanings stated under 1 (above), have also been found.

10. It has also been found that a benzylamine of the formula (VIII) in 9(above) is obtained when a compound of the general formula ##STR16## inwhich R¹ and n have the meanings stated under 5 (above), is reacted, ina first stage, with a cyanide salt and the nitrile thereby obtained, ofthe general formula ##STR17## is hydrogenated in a manner which is initself known.

11. A process has also been found for the preparation of a compound ofthe formula (XIII), (XI) or (IX), or of a similar compound,characterized in that

(a), in the case where two adjacent radicals R¹, together with the twoadjoining carbon atoms, form an oxygen-containing heterocyclicfive-membered ring which is substituted by fluorine, a compound havingthe general formula ##STR18## in which

n represents 1, 2, 3 or 4 and

each R¹ independently represents hydrogen, C₁₋₆ -alkyl,trihalogenomethyl, C₁₋₆ -alkoxy, C₁₋₆ -halogenoalkoxy with 1-6 halogenatoms, C₁₋₆ -alkylmercapto, C₁₋₆ -halogenoalkylmercapto with 1-6 halogenatoms, halogen, optionally substituted phenyl or phenoxy,chlorocarbonyl, chlorosulphonyl or nitro, or two adjacent radicals R¹,together with the adjoining carbon atoms, form an optionally substitutedfused-on benzene ring,

is obtained when a compound of the general formula ##STR19## in which R¹and n have the meanings stated above, is reacted with anhydroushydrofluoric acid, or

(b), in the case where two adjacent radicals R¹, together with the twoadjoining carbon atoms, form an oxygen-containing heterocyclicsix-membered ring which is substituted by fluorine, a compound havingthe general formula ##STR20## in which

n represents 1, 2, 3 or 4 and

each R¹ independently represents hydrogen, C₁₋₆ -alkyl, C₁₋₆-fluoroalkyl with 3-6 fluorine atoms, C₁₋₆ -alkoxy, C₁₋₆ -halogenoalkoxywith 1-6 halogen atoms, C₁₋₆ -alkylmercapto, C₁₋₆ -halogenoalkylmercaptowith 1-6 halogen atoms, C₂₋₆ -alkenyl, C₂₋₆ -alkynyl, halogen,optionally substituted phenyl or phenoxy, carboxyl, nitro, cyano or SO₃H, or two of the radicals R¹ denote a fused-on benzene ring and

X¹ represents hydrogen or halogen,

is obtained when a compound of the general formula ##STR21## in which R¹and n have the meanings stated above, is reacted with a compound of thegeneral formula ##STR22## in which

X² represents halogen and

X¹ represents hydrogen or halogen.

12. The new compounds of the general formula ##STR23## in which R¹, nand X¹ have the meanings stated under 11(b) (above), have also beenfound.

The compounds of the formula (I) exhibit good insecticidal properties.Surprisingly, these new active compounds according to the inventionexhibit a considerably higher activity than the compounds known from thestate of the art.

Preferred compounds of the formula (I) are those in which

n represents 1, 2, 3, 4 or 5,

each R¹ independently represents hydrogen, fluorine, chlorine, bromine,trifluoromethyl, methoxy, difluoromethoxy, trifluoromethoxy,tetrafluoroethoxy, hexafluoropropoxy, difluoromethylthio ortrifluoromethylthio, or phenyl or phenoxy, either of which may beoptionally substituted by halogen or alkoxy, or two adjacent radicalsR¹, together with the adjoining carbon atoms, form an oxygen-containingfive-membered or six-membered ring which is polysubstituted by fluorine,with the proviso that at least one of the radicals R¹ should denotefluoroalkoxy or fluoromethylthio, or that two of the radicals R¹ shouldrepresent OCF₂ O, OCF₂ CH₂ O or OCF₂ CHFO, thereby forming a 5-memberedor 6-membered heterocyclic ring with the two adjoining carbon atoms,

R² represents hydrogen, C₁ -C₄ -alkyl, cyano or ethynyl and

R³ represents the radical ##STR24## wherein

R⁴ and R⁵ are identical or different and represent fluorine, chlorine orbromine, or R⁴ and R⁵ both represent methyl, or

R³ represents the radical ##STR25## wherein R⁶ represents a phenyl ringwhich is optionally substituted by halogen, alkyl, alkylthio or alkoxywith in each case 1-4 carbon atoms, nitro or methylenedioxy, orrepresents a naphthyl radical.

Particularly preferred compounds of the formula (I) are those in which

each R¹ independently represents hydrogen, chlorine, difluoromethoxy,tetrafluoroethoxy, hexafluoropropoxy or trifluoromethylthio, or twoadjacent radicals R¹, together with the adjoining carbon atoms, form aheterocyclic oxygen-containing 5-membered or 6-membered ring, providedthat at least one R¹ should denote difluoromethoxy, tetrafluoroethoxy,hexafluoropropoxy or trifluoromethylthio, or that two adjacent radicalsR¹ should represent OCF₂ O, OCF₂ --CH₂ O or OCF₂ CHFO thereby forming a5-membered or 6-membered heterocyclic ring with the two adjoining carbonatoms,

R² represents hydrogen or cyano and

R³ represents the radical ##STR26## or the radical ##STR27## wherein R⁶represents a phenyl ring which is substituted by fluorine, chlorine,bromine, methoxy or methylenedioxy.

Specific compounds of the formula (I) which may be mentioned are thefollowing: 2-difluoromethoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-difluoromethoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,2-tetrafluoroethoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-tetrafluoroethoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-hexafluoropropoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-difluoromethoxy-4-chlorobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3,4-bis-(difluoromethoxy)-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-trifluoromethylthio-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-trifluoromethoxy-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-difluoromethylthio-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,3-difluoromethoxy-α-cyanobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxymethylene-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-2,3-dioxymethylene-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxymethylene-6-chlorobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxymethylene-6-bromobenzyl 2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxymethylene-2,5,6-trichlorobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxyethylene-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,trifluoro-3,4-dioxyethylene-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,difluoro-3,4-dioxyethylene-6-chlorobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,trifluoro-3,4-dioxyethylene-6-chlorobenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate,2-difluoromethoxybenzyl 4'-chlorophenyl-α-isopropylacetate,3-difluoromethoxybenzyl 4'-chlorophenyl-α-isopropylacetate,2-tetrafluoroethoxybenzyl 4'-chlorophenyl-α-isopropylacetate,3-tetrafluoroethoxybenzyl 4'-chlorophenyl-α-isopropylacetate,3-hexafluoropropoxybenzyl 4'-chlorophenyl-α-isopropylacetate,3-difluoromethoxy-4-chlorobenzyl 4'-chlorophenyl-α-isopropylacetate,3,4-bis-(difluoromethoxy)-benzyl 4'-chlorophenyl-α-isopropylacetate,3-trifluoromethylthio-benzyl 4'-chlorophenyl-α-isopropylacetate,3-trifluoromethoxy-benzyl 4'-chlorophenyl-α-isopropylacetate,3-trifluoromethylthio-benzyl 4'-chlorophenyl-α-isopropylacetate,3-difluoromethoxy-α-cyano-benzyl 4'-chlorophenyl-α-isopropylacetate,difluoro-3,4-dioxymethylenebenzyl 4'-chlorophenyl-α-isopropylacetate,difluoro-2,3-dioxymethylene-benzyl 4'-chlorophenyl-α-isopropylacetate,difluoro-3,4-dioxymethylene-6-chlorobenzyl4'-chlorophenyl-α-isopropylacetate,difluoro-3,4-dioxymethylene-6-bromobenzyl4'-chlorophenyl-α-isopropylacetate,difluoro-3,4-dioxymethylene-2,5,6-trichlorobenzyl4'-chlorophenyl-α-isopropylacetate, difluoro-3,4-dioxyethylene-benzyl4'-chlorophenyl-α-isopropylacetate, trifluoro-3,4-dioxyethylenebenzyl4'-chlorophenyl-α-isopropylacetate,difluoro-3,4-dioxyethylene-6-chlorobenzyl4'-chlorophenyl-α-isopropylacetate andtrifluoro-3,4-dioxyethylene-6-chlorobenzyl4'-chlorophenyl-α-isopropylacetate.

The preparation of the benzyl esters of the formula (I) according to theinvention can be represented by the equation which follows: ##STR28##

If, for example,2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylic acidchloride and difluoro-3,4-methylenedioxybenzyl alcohol are used asstarting materials in process variant (a) in 2 (above), the course ofthe reaction can be represented by the equation which follows: ##STR29##

The carbonyl halides of the formula (II) to be used as startingmaterials are known and can be prepared by the generally customaryprocesses described in the literature (see, for example, DT-OS (GermanPublished Specifications) Nos. 2,365,555; 1,926,433 and 2,231,312).

Specific examples which may be mentioned of the compounds of the formula(II) to be used as starting materials are:2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylic acidchloride, 2,2-dimethyl-3-(2',2'-dibromovinyl)-cyclopropanecarboxylicacid chloride,2,2-dimethyl-3-(2',2'-dimethylvinyl)-cyclopropanecarboxylic acidchloride, α-isopropyl-phenylacetic acid chloride,α-isopropyl-4-fluorophenylacetic acid chloride,α-isopropyl-4-chlorophenylaceticacid chloride,α-isopropyl-4-bromophenylacetic acid chloride,α-isopropyl-4-methylphenylacetic acid chloride,α-isopropyl-4-ethylphenylacetic acid chloride,α-isopropyl-4-n-propylphenylacetic acid chloride,α-isopropyl-4-isopropylphenylacetic acid chloride,α-isopropyl-4-methoxyphenylacetic acid chloride,α-isopropyl-4-ethoxyphenylacetic acid chloride,α-isopropyl-4-methylthiophenylacetic acid chloride,α-isopropyl-4-ethylthiophenylacetic acid chloride,α-isopropyl-4-nitrophenylacetic acid chloride,α-isopropyl-3-fluorophenylacetic acid chloride,α-isopropyl-3-bromophenylacetic acid chloride,α-isopropyl-3-chlorophenylacetic acid chloride,α-isopropyl-3-methylphenylacetic acid chloride,α-isopropyl-3-ethylphenylacetic acid chloride,α-isopropyl-3-methoxyphenylacetic acid chloride,α-isopropyl-3-ethoxyphenylacetic acid chloride,α-isopropyl-3-methylthiophenylacetic acid chloride,α-isopropyl-3-ethylthiophenylacetic acid chloride andα-isopropyl-3,4-methylenedioxyphenylacetic acid chloride.

The alcohols of the formula (III) also to be used as starting materialsare new.

The new alcohols can be prepared by the processes indicated under 4(above) (for details see below).

Specific examples which may be mentioned of alcohols of the formula(III) to be used as starting materials are: 2-difluoromethoxy-benzylalcohol, 3-difluoromethoxy-benzyl alcohol, 3-trifluoromethylthio-benzylalcohol, 3,4-difluoromethoxy-benzyl alcohol,3-difluoromethoxy-4-chloro-benzyl alcohol, 3-trifluoromethoxy-benzylalcohol, 3-trifluoromethylthio-benzyl alcohol,difluoro-3,4-dioxymethylene-benzyl alcohol,2-difluoromethoxy-α-cyano-benzyl alcohol,3-difluoromethoxy-α-cyano-benzyl alcohol,2-trifluoromethylthioα-cyano-benzyl alcohol,3,4-difluoromethoxy-α-cyano-benzyl alcohol,3-difluoromethoxy-4-chloro-α-cyano-benzyl alcohol,3-trifluoromethoxy-α-cyano-benzyl alcohol,3-trifluoromethylthio-α-cyano-benzyl alcohol,difluoro-3,4-dioxymethylene-α-cyano-benzyl alcohol,difluoro-3,4-dioxymethylene-α-ethynylbenzyl alcohol,3-difluoromethoxy-α-ethynyl-benzyl alcohol, 3-difluoromethylthio-benzylalcohol, 3-difluoromethylthio-α-cyano-benzyl alcohol and3-tetrafluoroethoxy-benzyl alcohol.

All the customary acid-binding agents can be used as acid acceptors forthe preparation of the compounds of the formula (I) from alcohols of theformula (III) and carbonyl halides of the formula (II). Alkali metalcarbonates and alcoholates, such as sodium carbonate and potassiumcarbonate and sodium methylate or ethylate and potassium methylate orethylate, and furthermore aliphatic, aromatic or heterocyclic amines,for example triethylamine, trimethylamine, dimethylaniline,dimethylbenzylamine and pyridine, have proved particularly suitable.

The reaction temperature can be varied within a substantial range. Ingeneral, the reaction is carried out at from 0° to 100° C., preferablyat from 15° to 40° C.

In general, the reaction is allowed to proceed under normal pressure.The process for the preparation of the compounds of the formula (I) ispreferably carried out also using a suitable solvent or diluent.Virtually any inert organic solvent can be used as the solvent ordiluent, especially aliphatic and aromatic, optionally chlorinated,hydrocarbons, such as benzene, toluene, xylene, benzine, methylenechloride, chloroform, carbon tetrachloride and chlorobenzene; ethers,for example diethyl ether, dibutyl ether and dioxane; ketones, forexample acetone, methyl ethyl ketone, methyl isopropyl ketone and methylisobutyl ketone; and nitriles, such as acetonitrile and propionitrile.

The starting materials are preferably employed in equimolar amounts forcarrying out the process. An excess of one or other of the componentsprovides no substantial advantages. In general, the reactants arebrought together in one of the solvents indicated and the mixture isusually stirred for one or more hours at elevated temperature in orderto bring the reaction to completion. The reaction mixture is then pouredinto water and the organic phase is separated off and rinsed with water.After drying, the solvent is distilled off in vacuo.

The new compounds are obtained in the form of oils, some of which cannotbe distilled without decomposition, but which can be freed from the lastvolatile constituents by so-called "incipient distillation", that is tosay by prolonged heating to moderately elevated temperatures underreduced pressure, and can be purified in this manner. The refractiveindex is used for their characterization.

The compounds of the formula (I) are also obtained by reacting the saltsof carboxylic acids (IV) with benzyl halides (V): ##STR30##

If, for example, the potassium salt of 4-chlorophenylacetic acid (whichcan appropriately be prepared "in situ" from the acid and KOH) and3-difluoromethoxy-benzyl bromide are used as starting substances inprocess variant (b) in 2 (above), the course of the reaction can berepresented by the equation which follows: ##STR31##

The carboxylic acids of their salts of the formula (IV) to be used asstarting materials are known, and the carbonyl halides of the formula(II) are based on them. All the acids and salts on which the acidhalides of the formula (II) are based can thus be used for thepreparative procedure mentioned above.

Specific examples which may be mentioned are the acids, and theirsodium, potassium, calcium or ammonium salts, on which the acid halideslisted above are based.

Benzyl halides of the formula (V) used as starting materials are knownand can be obtained by processes indicated below.

Specific benzyl halides (V) which may be mentioned are the following:2-difluoromethoxybenzyl chloride, 3-difluoromethoxybenzyl chloride,3-difluoromethoxy-4-chlorobenzyl bromide, 3-trifluoromethoxy-benzylbromide, difluoro-3,4-dioxymethylenebenzyl chloride,difluoro-3,4-dioxymethylenebenzyl bromide,difluoro-3,4-dioxymethylene-6-chlorobenzyl bromide,difluoro-3,4-dioxymethylene-6-bromobenzyl bromide,difluoro-3,4-dioxymethylene-α-cyanobenzyl bromide,difluoro-2,3-dioxymethylene-benzyl chloride,difluoro-2,3-dioxymethylene-benzyl bromide, 3-tetrafluoroethoxy-benzylchloride, 3-tetrafluoroethoxy-benzyl bromide anddifluoro-3,4-dioxymethylene-2,5,6-trichlorobenzyl chloride.

A solvent such as an aromatic, optionally chlorinated hydrocarbon, forexample benzene, toluene, xylene, chlorobenzene or dichlorobenzene, isgenerally used for the preparation of the compounds of the formula (I)from the salts of carboxylic acids, of the formula (IV), and the benzylhalides of the formula (V).

The salts of the carboxylic acids can be employed direct, or can beprepared "in situ" by adding KOH or NaOH in the form of their aqueoussolutions or in the powdered form. Quaternary ammonium salts, forexample tetrabutylammonium chloride, tetrabutylammonium bromide,benzyltriethylammonium chloride or methyltrioctylammonium chloride, canbe used as catalysts.

The reaction temperature can be varied within a substantial range. Ingeneral, the reaction is carried out at from 50° to 150° C., preferablyat from 30° to 120° C.

The starting materials are preferably employed in equimolar amounts forcarrying out the process. An excess of the salt of the acid can be usedin order to achieve complete reaction of the benzyl halide. The excessacid can be recovered from the aqueous phase. In most cases, thereaction has ended after 1-5 hours. After cooling the reaction mixture,water is added and the organic phase is separated off and washed untilneutral. The solvent is then distilled off in vacuo and the compounds ofthe formula (I) are purified as described above.

As already mentioned, the alcohols of the formula (III) are new. Theycan be prepared by the processes indicated under 4 (above).

In variant 4(a), in the case where R² in the desired compound of theformula (III) represents hydrogen, the corresponding aldehyde is reducedwith hydrogen. This reaction can be represented by the equation whichfollows: ##STR32##

Possible reducing agents are hydrogen in the presence of a catalyst, orcomplex metal hydrides, for example sodium borohydride or lithiumaluminum hydride. The reaction is carried out analogously to knownprocesses (see Organikum, VEB Deutscher Verlag der Wissenschaften,Berlin 1965, 5th edition, page 417; and J. Am. Chem. Soc. 71, 122(1949); 75, 199 (1953) and 76, 6116 (1954)).

In the case where R² in the desired compound of the formula (III)represents CN, the corresponding aldehyde is reacted with HCN. Thisreaction can be represented by the equation which follows: ##STR33##

The reaction is carried out analogously to the known processes for thepreparation of cyanohydrins (see Organic Syntheses; Coll. Volume I, 336;and Houben-Weyl Volume VIII, page 274 et seq.).

In the case where R² in the desired compound of the formula (III)represents C₁₋₄ -alkyl or ethynyl, the corresponding aldehyde is reactedwith a Grignard compound of the formula (VII). This reaction can berepresented by the equation which follows: ##STR34##

The reaction is carried out analogously to the methods described in, forexample, Org. Synth. Coll. Volume IV, page 792.

The Grignard compounds of the formula (VII) are known (see, for example,the literature reference indicated above).

Specific aldehydes of the formula (VI) which may be mentioned are thefollowing: 2-difluoromethoxy-benzaldehyde,2-trifluoromethylthio-benzaldehyde, 3-difluoromethoxy-benzaldehyde,3,4-bis-difluoromethoxy-benzaldehyde,3-difluoromethoxy-4-chloro-benzaldehyde,3-trifluoromethoxy-benzaldehyde, 3-trifluoromethylthio-benzaldehyde anddifluoro-3,4-dioxymethylene-benzaldehyde.

Aldehydes of the formula (VI) are known (see, for example, J. Org. Chem.37 (673 (1972) and Z. obsc. Chim. 30, 3129 (1960)), and can be preparedby known processes. The difluoromethoxy compounds are obtained, forexample, from the corresponding phenols with difluorochloromethane inthe presence of bases (see, for example, DOS (German PublishedSpecification) No. 2,150,955 and J. Org. Chem. 25, 2009 (1960)).

Aldehydes of the formula (VI) can be obtained by dihalogenating,preferably dichlorinating, the compounds of the formula (XI) in 8(above) in the side chain in a manner which is in itself known andsaponifying, in a manner which is in itself known, the compounds thusobtained. Specific compounds of the formula (XI) which may be mentionedare the following: trifluoro-3,4-dioxyethylenetoluene,difluoro-3,4-dioxyethylenetoluene, trifluoro-2,3-dioxyethylenetolueneand trifluoro-3,4-dioxyethylene-6-chloro-toluene.

In variant 4(b), benzylamines of the formula (VIII) are reacted withnitrous acid in the presence of an acid, for example acetic acid. Thisreaction can be represented by the equation which follows: ##STR35##

The benzylamines of the formula (VIII) used in this reaction are new,and are obtained by reducing the corresponding nitriles with hydrogenanalogously to known processes (Houben-Weyl, Volume XI/1, page 577). Thenitriles are obtained, for example, by reacting the correspondingbromine compounds with copper(I) cyanide analogously to known processes(Houben-Weyl, Volume VIII, page 302). If, for example, two radicals R¹together denote OCF₂ O and R² represents hydrogen, the entire course ofthe reaction can be represented by the equation which follows: ##STR36##

In variant, 4(c), the benzyl halides of the formula (V) are saponified.This reaction can be represented by the equation which follows:##STR37##

The saponification is carried out in a manner which is in itself knownusing aqueous bases, for example NaOH, KOH or alkali metal carbonates,such as Na₂ CO₃ or K₂ CO₃.

Benzyl halides of the formula (V) used in processes 2(b) and 4(c)(above) are obtainable, for example, as indicated under 6 (above) byhalogenating, in particular brominating or chlorinating, compounds ofthe general formula ##STR38## by methods which are known in principle.

Examples of possible halogenating agents are chlorine or N-chloro- orN-bromo-succinimide.

The chlorination or bromination of the above-mentioned compounds to givethe corresponding benzyl chlorides or bromides is carried out in amanner which is in itself known under free radical conditions usingchlorine, N-chlorosuccinimide or N-bromo-succinimide in a solvent, forexample methylene chloride, chloroform, carbon tetrachloride,chlorobenzene or o-difluorobenzene, preferably at elevated temperature.

Specific starting compounds of the formula (IX) which may be mentionedare: 2-difluoromethoxytoluene, 2-difluoromethoxy-6-chloro-toluene,3-difluoromethoxy-toluene, 3-difluoromethoxy-4-chloro-toluene,3-difluoromethoxy-6-chlorotoluene, 3,4-difluoromethoxy-toluene,2,3-difluoromethoxytoluene, difluoro-3,4-dioxymethylene-toluene,difluoro-3,4-dioxymethylene-6-chloro-toluene,difluoro-2,3-dioxymethylenetoluene, trifluoro-3,4-dioxyethylene-toluene,difluoro-3,4-dioxyethylenetoluene, trifluoro-2,3-dioxyethylenetoluene,difluoro-2,3-dioxyethylenetoluene, 3-trifluoromethylthiotoluene,1-n-propyl-difluoro-3,4-methylenedioxy-benzene,3-tetrafluoroethoxy-toluene and 3-hexafluoropropoxy-toluene. Startingcompounds mentioned for the processes in 6, 8 and 10 (above) can beobtained, for example, by the process indicated under 11(a) (above).

The compounds of the formula (XIV) in which one radical R¹ denotes C₁₋₆-alkyl and the other radicals R¹ represent identical or differentradicals from the group comprising hydrogen, C₁₋₆ -alkoxy, C₁₋₆-halogenoalkoxy with 1-6 halogen atoms, C₁₋₆ -alkylmercapto, C₁₋₆-halogenoalkylmercapto with 1-6 halogen atoms, halogen and optionallysubstituted phenyl, or two adjacent radicals, together with theadjoining carbon atoms, form an optionally substituted fused-on benzenering, are preferred.

The compounds (XIV) in which one radical R¹ denotes methyl and the otherradicals R¹ represent identical or different radicals from the groupcomprising hydrogen and halogen are very particularly preferred.

Specific examples which may be mentioned are:difluoro-3,4-dioxymethylene-toluene,difluoro-3,4-dioxymethylene-6-fluoro-toluene,difluoro-3,4-dioxymethylene-6-chlorotoluene,difluoro-3,4-dioxymethylene-6-bromo-toluene,difluoro-3,4-dioxymethylene-2,5,6-trichlorotoluene,difluoro-3,4-dioxymethylene-2,5,6-trifluorotoluene anddifluoro-2,3-dioxymethylene-toluene.

It is known to obtain 2,2-difluorobenzodioxoles from2,2-dichlorobenzodioxoles by reaction with antimony trifluoride (Z.obsc. Khim. 30 (1960) No. 9, 3129-3132). However, this is not a processwhich can be utilized industrially, since antimony trifluoride is ratherexpensive and, in the method mentioned, is converted into aqueoussolutions of antimony chlorides which cannot be recovered withouteffort.

It has now been found that compounds of the formula (XIV) in 11 (above)are obtained when compounds of the formula ##STR39## in which R¹ and nhave the meanings indicated in 11(a) (above) are reacted with anhydroushydrofluoric acid.

Starting substances of the formula (XV) can be prepared from thecorresponding benzodioxoles (J. Chem. Soc. 93, 566 (1908)), thecorresponding catechol carbonates (Chem. Ber. 96, 1382 (1963)) or thecorresponding catechol orthoformates (Chem. Ber. 94, 544 (1961)) byreaction with PCl₅.

Starting substances of the formula (XV) in which R¹ represents identicalor different radicals from the group comprising hydrogen, C₁₋₄ -alkyl,such as methyl, ethyl, n-propyl, i-propyl or t-butyl, trichloromethyl,fluorine, chlorine, bromine, phenyl which is optionally substituted byhalogen or C₁₋₄ -alkyl, for example methyl, chlorocarbonyl,chlorosulphonyl and nitro, or two adjacent radicals, together with theadjoining carbon atoms, form a fused-on benzene ring, are preferablyemployed.

Specific examples of the starting substances of the formula (XV) whichmay be mentioned are: 2,2-dichlorobenzodioxole,4-methyl-2,2-dichlorobenzodioxole, 5-methyl-2,2-dichlorobenzodioxole,5-ethyl-2,2-dichlorobenzodioxole, 5-propyl-2,2-dichlorobenzodioxole,5-isopropyl-2,2-dichlorobenzodioxole,4-methyl-2,2,5,6-tetrachlorobenzodioxole,5-methyl-2,2,6-trichlorobenzodioxole,5-methyl-2,2,4,6-tetrachlorobenzodioxole,5-propyl-2,2,6-trichlorobenzodioxole,5-methyl-6-bromo-2,2-dichlorobenzodioxole,5-fluoro-2,2-dichlorobenzodioxole, 5-bromo-2,2-dichlorobenzodioxole,2,2,5-trichlorobenzodioxole, 4-phenyl-2,2-dichlorobenzodioxole,5-phenyl-2,2-dichlorobenzodioxole, 4-methoxy-2,2-dichlorobenzodioxole,5-methoxy-2,2-dichlorobenzodioxole, 4-phenoxy-2,2-dichlorobenzodioxole,5-(3'-methyl)-phenoxy-2,2-dichlorobenzodioxole,4-(4'-nitro)-phenoxy-2,2-dichlorobenzodioxole,5-tert.-butyl-2,2-dichlorobenzodioxole,5-chloro-6-nitro-2,2-dichlorobenzodioxole,2,2,4,6-tetrachlorobenzodioxole, 2,2,5,6-tetrachlorobenzodioxole,5-methyl-2,2,4,6,7-pentachloro-benzodioxole,4-chlorocarbonyl-2,2-dichlorobenzodioxole,5-chlorocarbonyl-2,2-dichlorobenzodioxole,5-nitro-2,2-dichlorobenzodioxole, 2,2-dichloronaphtho-2,3-dioxole and2,2-dichloro-naphtho-1,2-dioxole.

The reaction in the process variant 11(a) can be carried out attemperatures from -20° C. to 80° C., and preferably at temperatures from0° C. to 40° C.

The hydrofluoric acid must be employed in at least stoichiometricamounts, and in fact an excess is generally favorable. Thus, the amountof hydrofluoric acid is preferably twice to three times thestoichiometric amount, but the excess can be greater. The reaction canbe carried out in the presence of solvents and also without solvents.Possible solvents are, quite generally, inert, aprotic liquids. Forexample, methylene chloride, trichlorofluoromethane, carbontetrachloride, chlorobenzene or nitrobenzene can successfully be used.The amount of solvent is not important for the process according to theinvention. Thus, the reaction is preferably carried out without asolvent if the starting materials are liquid.

In general, the reaction is carried out under normal pressure, but itcan also be carried out under increased pressure.

The process according to the invention can, for example, be carried outas follows:

The required amount of anhydrous hydrofluoric acid is initiallyintroduced into the reaction vessel at about -10° C. and the2,2-dichlorobenzodioxole is added dropwise, while stirring. Thetemperature is chosen so that evolution of hydrogen chloride startsimmediately, and the gas formed is passed, via a reflux condenser, to areceiver, where it is condensed or neutralized. When the addition hasended, the temperature can be increased slightly. The mixture is stirreduntil the evolution of gas has ended, and the excess hydrofluoric acidis then distilled off under normal pressure or reduced pressure. Thereaction product remains as the residue and can then be purified, forexample by distillation.

Compared with known processes for the preparation of2,2-difluorobenzodioxoles, the process according to the invention hasthe advantage that it is simple to carry out and gives rise to noecologically unacceptable effluents. Furthermore, the excessfluorinating agent can be recovered in a simple manner and employedagain in the reaction.

The other starting compounds mentioned in the processes in 6, 8 and 10(above) and similar compounds can be obtained, for example, by theprocess indicated under 11(b) (above).

In this process, catechols of the general formula ##STR40## in which R¹and n have the meanings indicated under 11(b) (above), are reacted withcompounds of the general formula ##STR41## in which

X² represents halogen, preferably F or Cl, and

X¹ represents hydrogen or halogen, preferably F or Cl,

in the presence of a base.

If 4-methylcatechol and trifluorochloroethylene are used as startingmaterials, the course of the reaction can be represented by the equationwhich follows: ##STR42##

Catechols of the formula (XVII) in which (R¹)_(n) represents identicalor different radicals from the group comprising hydrogen, C₁₋₄ -alkyl,in particular methyl, ethyl or t-butyl, fluorine, chlorine, bromine,phenyl which is optionally substituted by C₁₋₄ -alkyl, in particularmethyl, or halogen, in particular chlorine or bromine, carboxyl (COOH),nitro, CN or SO₃ H, or two of the radicals R¹, together with theadjoining carbon atoms, form a fused-on benzene ring, may be mentionedas preferred starting materials.

Specific compounds of the formula (XVII) which may be mentioned are thefollowing: catechol, 3-methylcatechol, 4-methylcatechol,4-tert.-butyl-catechol, 4-chloro-catechol, 4-bromo-catechol,3,5-dichlorocatechol, 4,5-dichlorocatechol, 3,4,5-trichlorocatechol,tetrachlorocatechol, 3,4-dihydroxybiphenyl, 2,3-naphthalenediole,4-methyl-5-chlorocatechol, 4-methyl-3,5,6-trichlorocatechol,2,3-dihydroxy-benzoic acid, 3,4-dihydroxy-sulphonic acid,4-nitrocatechol, 4-cyanocatechol and 2,3-dihydroxyterephthalic acid.

Specific examples of compounds of the formula (XVIII) which may bementioned are: chlorotrifluoroethylene, tetrafluoroethylene,bromotrifluoroethylene, chlorodifluoroethylene,1,1-dichloro-2,2-difluoroethylene and bromodifluoroethylene.

Chlorotrifluoroethylene and chlorodifluoroethylene are particularlypreferred.

Suitable bases are, in particular, the hydroxides of the alkali metalsand alkaline earth metals, but also the carbonates of these metals. Theamount of base can vary between one and more than three moles per moleof pyrocatechol. An excess has a favorable effect. The reaction can becarried out at temperatures from 20° C. to 150° C., particularlypreferably in the range from 80° to 120° C. A polar liquid is used asthe solvent. Examples of solvents which have proved suitable are:dimethylsulphoxide, dimethylformamide and tetramethylenesulphone, andalso ethers, such as dioxane, or diglyme. Tetramethylenesulphone ispreferred.

The reaction is carried out under normal pressure or under increasedpressure, in order to prevent the fluorinated ethylenes escaping if theydo not react immediately when metered in. In general, the reaction iscarried out between 1 and 30 bars, preferably between 1 and 15 bars.

The process according to the invention can be carried out under 1 bar asfollows:

The catechol, dissolved in the solvent is initially introduced into thereaction vessel, the base is added and the mixture is warmed to thereaction temperature (for example 100° C.), while stirring. After abouthalf an hour, the fluorinated ethylene is then passed in at the rate atwhich it is taken up by the reaction solution. Towards the end of thereaction, non-consumed olefin passes through and can be recycled againinto the reaction. If the reaction is carried out under increasedpressure, the catechols, bases and solvents are initially introducedinto a pressure vessel, the mixture is warmed to the reactiontemperature and the ethylenes of the formula (XVIII) are then pumped inat a rate such that the desired pressure is established.

When the reaction has ended, the mixture is worked up either byfractional distillation or by diluting with water and separating off thereaction product.

As already mentioned, the compounds of the formula (I) exhibitinsecticidal activity.

The active compounds are well tolerated by plants, have a favorablelevel of toxicity to warm-blooded animals, and can be used for combatingarthropod pests, especially insects, which are encountered inagriculture, in forestry, in the protection of stored products and ofmaterials, and in the hygiene field. They are active against normallysensitive and resistant species and against all or some stages ofdevelopment. The above-mentioned pests include:

from the class of the Isopoda, for example Oniscus asellus,Armadillidium vulgare and Porcellio scaber;

from the class of the Diplopoda, for example Blaniulus guttulatus;

from the class of the Chilopoda, for example Geophilus carpophagus andScutigera spec.;

from the class of the Symphyla, for example Scutigerella immaculata;

from the order of the Thysanura, for example Lepisma saccharina;

from the order of the Collembola, for example Onychiurus armatus;

from the order of the Orthoptera, for example Blatta orientalis,Periplaneta americana, Leucophaea maderae, Blattella germanica, Achetadomesticus, Gryllotalpa spp., Locusta migratoria migratoroioides,Melanoplus differentialis and Schistocera gregaria;

from the order of the Dermaptera, for example Forficula auricularia;

from the order of the Isoptera, for example Reticulitermes spp.;

from the order of the Anoplura, for example Phylloxera vastatrix,Pemphigus spp., Pediculus humanus corporis, Haematopinus spp. andLinognathus spp.;

from the order of the Mallophaga, for example Trichodectes spp. andDamalinea spp.;

from the order of the Thysanoptera, for example Hercinothrips femoralisand Thrips tabaci;

from the order of the Heteroptera, for example Eurygaster spp.,Dysdercus intermedius, Piesma quadrata, Cimex lectularius, Rhodniusprolixus and Triatoma spp.;

from the order of the Homoptera, for example Aleurodes brassicae,Bemisia tabaci, Trialeurodes vaporariorum, Aphis gossypii, Brevicorynebrassicae, Cryptomyzus ribis, Doralis fabae, Doralis pomi, Eriosomalanigerum, Hyalopterus arundinis, Macrosiphum avenae, Myzus spp.,Phorodon humuli, Rhopalosiphum padi, Empoasca spp., Euscelis bilobatus,Nephotettix cincticeps, Lecanium corni, Saissetia oleae, Laodelphaxstriatellus, Nilaparvata lugens, Aonidiella aurantii, Aspidiotushederae, Pseudococcus spp. and Psylla spp.;

from the order of the Lepidoptera, for example Pectinophora gossypiella,Bupalus piniarius, Cheimatobia brumata, Lithocolletis blancardella,Hyponomeuta padella, Plutella maculipennis, Malacosoma neustria,Euproctis chrysorrhoea, Lymantria spp., Bucculatrix thurberiella,Phyllocnistis citrella, Agrotis spp., Euxoa spp., Feltia spp., Eariasinsulana, Heliothis spp., Laphygma exigua, Mamestra brassicae, Panolisflammea, Prodenia litura, Spodoptera spp., Trichoplusia ni, Carpocapsapomonella, Pieris spp., Chilo spp., Pyrausta nubilalis, Ephestiakuehniella, Galleria mellonella, Cacoecia podana, Capua reticulana,Choristoneura fumiferana, Clysia ambiguella, Homona magnanima andTortrix viridana;

from the order of the Coleoptera, for example Anobium punctatum,Rhizopertha dominica, Bruchidius obtectus, Acanthoscelides obtectus,Hylotrupes bajulus, Agelastica alni, Leptinotarsa decemlineata, Phaedoncochleariae, Diabrotica spp., Psylliodes chrysocephala, Epilachnavarivestis, Atomaria spp., Oryzaephilus surinamensis, Anthonomus spp.,Sitophilus spp., Otiorrhynchus sulcatus, Cosmopolites sordidus,Ceuthorrhynchus assimilis, Hypera postica, Dermestes spp., Trogodermaspp., Anthrenus spp., Attagenus spp., Lyctus spp., Meligethes aeneus,Ptinus spp., Niptus hololeucus, Gibbium psylloides, Tribolium spp.,Tenebrio molitor, Agriotes spp., Conoderus spp., Melolontha melolontha,Amphimallon solstitialis and Costelytra zealandica;

from the order of the Hymenoptera, for example Diprion spp., Hoplocampaspp., Lasius spp., Monomorium pharaonis and Vespa spp.;

from the order of the Diptera, for example Aedes spp., Anopheles spp.,Culex spp., Drosophila melanogaster, Musca spp., Fannia spp., Calliphoraerythrocephala, Lucilia spp., Chrysomyia spp., Cuterebra spp.,Gastrophilus spp., Hyppobosca spp., Stomoxys spp., Oestrus spp.,Hypoderma spp., Tabanus spp., Tannia spp., Bibio hortulanus, Oscinellafrit, Phorbia spp., Pegomyia hyoscyami, Ceratitis capitata, Dacus oleaeand Tipula paludosa;

from the order of the Siphonaptera, for example Xenopsylla cheopis andCeratophyllus spp.

The active compounds can be converted into the customary formulations,such as solutions, emulsions, wettable powders, suspensions, powders,dusting agents, foams, pastes, soluble powders, granules, aerosols,suspension-emulsion concentrates, seed-treatment powders, natural andsynthetic materials impregnated with active compound, very fine capsulesin polymeric substances, coating compositions for use on seed, andformulations used with burning equipment, such as fumigating cartridges,fumigating cans and fumigating coils, as well as ULV cold mist and warmmist formulations.

These formulations may be produced in known manner, for example bymixing the active compounds with extenders, that is to say liquid orliquefied gaseous or solid diluents or carriers, optionally with the useof surface-active agents, that is to say emulsifying agents and/ordispersing agents and/or foam-forming agents. In the case of the use ofwater as an extender, organic solvents can, for example, also be used asauxiliary solvents.

As liquid diluents or carriers, especially solvents, there are suitablein the main, aromatic hydrocarbons, such as xylene, toluene or alkylnaphthalenes, chlorinated aromatic or chlorinated aliphatichydrocarbons, such as chlorobenzenes, chloroethylenes or methylenechloride, aliphatic or alicyclic hydrocarbons, such as cyclohexane orparaffins, for example mineral oil fractions, alcohols, such as butanolor glycol as well as their ethers and esters, ketones, such as acetone,methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, orstrongly polar solvents, such as dimethylformamide anddimethylsulphoxide, as well as water.

By liquefied gaseous diluents or carriers are meant liquids which wouldbe gaseous at normal temperature and under normal pressure, for exampleaerosol propellants, such as halogenated hydrocarbons as well as butane,propane, nitrogen and carbon dioxide.

As solid carriers there may be used ground natural minerals, such askaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite ordiatomaceous earth, and ground synthetic minerals, such ashighly-dispersed silicic acid, alumina and silicates. As solid carriersfor granules there may be used crushed and fractionated natural rockssuch as calcite, marble, pumice, sepiolite and dolomite, as well assynthetic granules of inorganic and organic meals, and granules oforganic material such as sawdust, coconut shells, corn cobs and tobaccostalks.

As emulsifying and/or foam-forming agents there may be used non-ionicand anionic emulsifiers, such as polyoxyethylene-fatty acid esters,polyoxyethylene-fatty alcohol ethers, for example alkylaryl polyglycolethers, alkyl sulphonates, alkyl sulphates, aryl sulphonates as well asalbumin hydrolysis products. Dispersing agents include, for example,lignin sulphite waste liquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latices, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, can be used in theformulations.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs or metal phthalocyaninedye-stuffs, and trace nutrients, such as salts of iron, manganese,boron, copper, cobalt, molybdenum and zinc.

The formulations in general contain from 0.1 to 95 percent by weight ofactive compound, preferably from 0.5 to 90 percent by weight.

The active compounds according to the invention may be used in the formof their formulations of the types that are commercially available or inthe use forms prepared from these formulations.

The active compound content of the use forms prepared from theformulations of the types that are commercially available can varywithin wide ranges. The active compound concentration of the use formscan be from 0.0000001 to 100% by weight of active compound, preferablyfrom 0.01 to 10% by weight.

The compounds may be employed in a customary manner appropriate for theparticular use forms.

When used against pests harmful to health and pests of stored products,the active compounds are distinguished by an excellent residual activityon wood and clay as well as a good stability to alkali on limedsubstrates.

In the veterinary field, the active compounds according to the inventionmay be used in a known manner, such as orally in the form of, forexample, tablets, capsules, drenches and granules; dermally by means of,for example, dipping, spraying, pouring-on, spotting-on and powdering;and parenterally, for example by means of injections.

The present invention also provides an arthropodicidal compositioncontaining as active ingredients a compound of the present invention inadmixture with a solid or liquefied gaseous diluent or carrier or inadmixture with a liquid diluent or carrier containing a surface-activeagent.

The present invention also provides a method of combating arthropods,especially insects, which comprises applying to the arthropods, or to ahabitat thereof, a compound of the present invention alone or in theform of a composition containing as active ingredient a compound of thepresent invention in admixture with a diluent or carrier.

The present invention also provides a method of freeing or protectingdomesticated animals from parasitical insects which comprises applyingto said animals a compound according to the present invention, inadmixture with a diluent or carrier.

The present invention further provides crops protected from damage byarthropods by being grown in areas in which immediately prior to and/orduring the time of the growing a compound of the present invention wasapplied alone or in admixture with a diluent or carrier.

It will be seen that the usual methods of providing a harvested crop maybe improved by the present invention.

The present invention further provides domesticated animals wheneverfreed or protected from parasitical insects by the application to saidanimals of a compound according to the present invention, in admixturewith a diluent or carrier.

Preparation of the novel compounds is shown in the followingillustrative examples:

EXAMPLE 1 (A) Preparation of the starting substances

(i) 2-Difluoromethoxybenzyl alcohol

51.5 g (0.3 mol) of 2-difluoromethoxybenzaldehyde were dissolved in 100ml of ethanol, and 6.25 g of sodium borohydride in 100 ml of ethanolwere added dropwise at 25°-35° C. The mixture was then further stirreduntil room temperature was reached and was diluted with water andacidified with 25% strength H₂ SO₄. After extracting twice withmethylene chloride, the organic phase was dried and the solvent wasdistilled off. A colorless oil was obtained in almost quantitative yieldand, ater some time, solidified. The 2-difluoromethoxybenzyl alcoholmelted at 42° C.

(ii) 2- and 3-Trifluoromethylthiobenzyl alcohol

These were obtained from 2- and 3-trifluoromethylthiobenzaldehydeanalogously to (i).

(iii) 2-Difluoromethoxy-α-cyano-benzyl alcohol

7.2 g of potassium cyanide were dissolved in 30 ml of water and 6 ml ofethanol, while cooling. 16 g of 2-difluoromethoxybenzaldehyde were thenadded at 0°-5° C., while cooling. After subsequently stirring themixture between 0° and 10° C. for 20 minutes, a mixture of 7 ml ofconcentrated H₂ SO₄ and 18 ml of water was added dropwise. The mixturewas subsequently stirred for a further 2 hours and was thereby allowedto come to room temperature. After extracting twice with methylenechloride, the organic phase was dried and the solvent was distilled off.2-Difluoromethoxy-α-cyano-benzyl alcohol was obtained as a colorlessoil, the structure of which was confirmed by a nuclear magneticresonance spectrum. The yield was virtually quantitative.

(iv) Analogously to (iii), 2-trifluoromethylthio-α-cyano-benzyl alcoholwas obtained from 2-trifluoromethylthio-benzaldehyde anddifluoro-3,4-dioxymethylene-α-cyano-benzyl alcohol was obtained fromdifluoro-3,4-dioxymethylene-benzaldehyde.

(v) Analogously to (i), difluoro-3,4-dioxymethylene-benzyl alcohol wasobtained from difluoro-3,4-dioxymethylenebenzaldehyde by reduction withsodium borohydride. The NMR spectrum (in CDCl₃) confirmed the structure:3.7 ppm (s, OH); 4.6 ppm (s, CH₂); and 7.0 ppm and 7.05 ppm (3. aromaticH).

(vi) Difluoro-3,4-methylenedioxy-toluene

200 ml of HF (anhydrous) were initially introduced into the reactionvessel at 0° C. and 190 g of dichloro-3,4-methylenedioxytoluene (see J.Chem. Soc. 93, 563) were added dropwise. When the evolution of hydrogenchloride had ended, the mixture was warmed to 20° C. and stirred for 1hour and excess hydrofluoric acid was then distilled off under reducedpressure. Difluoro-3,4-methylenedioxytoluene boiled at 74°-78° C./52 mm(n_(d) ²⁰ =1.492).

(vii) 1-n-Propyl-difluoro-3,4-methylenedioxy-benzene was obtainedanalogously to the above instructions. Boiling point=80°/15 mm Hg (n_(D)²⁰ =1.4540).

(viii) Difluoro-3,4-methylenedioxy-benzyl bromide

172 g (1 mol) of difluoro-3,4-methylenedioxytoluene, 180 g ofN-bromosuccinimide and a pinch of azobisisobutyronitrile were mixed with1,000 ml of CCl₄ and the mixture was heated to the boil for 5 hours.After cooling, it was filtered, the residue was rinsed with a littleCCl₄ and the filtrate was distilled. 180 g (72% of theory) ofdifluoro-3,4-methylenedioxy-benzyl bromide of boiling point=180°-111°C./15 mm Hg and refractive index n_(D) ²⁰ =1.518 were obtained.

(ix) 1-Bromo-1-(difluoro-3,4-methylenedioxy)-phenylpropane of boilingpoint 70°-73° C./0.3 mm Hg were obtained analogously to (viii).

(x) Difluoro-3,4-methylenedioxy-6-chloro-benzyl bromide

14 g of chlorine were passed into a solution of 34.4 g (0.2 mol) ofdifluoro-3,4-methylenedioxy-toluene in 40 ml of methylene chloride at-10° C. to -5° C. The mixture was allowed to come to room temperatureand was fractionated under a waterpump vacuum. 31 g ofdifluoro-3,4-methylene-dioxy-6-chloro-toluene of boiling point80°-84°/15 mm Hg were obtained and were dissolved in 150 ml of carbontetrachloride. After adding 33 g of N-bromo-succinimide and a pinch ofazibisisobutyronitrile, the mixture was heated to the boil for 5 hours.30 g of difluoro-3,4-methylenedioxy-6-chloro-benzyl bromide of boilingpoint 74°-75° C./0.25 mm Hg and refractive index n_(D) ²⁰ of 1.5334 wereobtained.

(xi) Trifluoro-3,4-dioxyethylene-benzyl bromide

124 g of 4-methylpyrocatechol were dissolved in 300 ml of tetramethylenesulphone, and 110 g of KOH were added. 170 g of trifluorochloroethylenewere then passed in at 100° to 110° C. After cooling, the mixture wasdistilled over a column, under a waterpump vacuum. 132 g oftrifluoro-3,4-dioxyethylene-toluene of boiling point 70°-72° C./12 mm Hgand n_(D) ²⁰ of 1.4565 were obtained.

50 g of the product were brominated with 50 g of N-bromosuccinimide in150 ml of CCl₄ analogously to the above instructions (8 hours underreflux). The trifluoro-3,4-dioxyethylene-benzyl bromide boiled at123°-124° C./13 mm Hg; refractive index n_(D) ²⁰ =1.5165.

(xii) 4-Methyl-2,2-difluorobenzodioxole

200 ml of HF were initially introduced into the reaction vessel at 0° C.and 100 g of 4-methyl-2,2-dichlorobenzodioxole were added dropwise. Whenthe evolution of hydrogen chloride had ended, the mixture was warmedfurther to 20° C., and subsequently stirred for 1 hour and the excesshydrofluoric acid was then distilled off under reduced pressure. The4-methyl-2,2-difluorobenzodioxole had a boiling point of 42°-45° C./11mm Hg (n_(D) ²⁰ : 1.4515).

4-Bromomethyl-2,2-difluorobenzodioxole boiled at 93°-96° C./10 mm Hg(n_(D) ²⁰ =1.5115).

(xiii) 5-Propyl-2,2-difluorobenzodioxole

100 ml of anhydrous hydrofluoric acid were initially introduced into thereaction vessel at -2° C. and 110 g of 5-propyl-2,2-dichlorobenzodioxolewere then added dropwise. After carrying out the reaction analogously toxv(a), infra, 67 g of 5-propyl-2,2-difluorobenzodioxole with a boilingpoint ef 80°-83° C./15 mm Hg (n_(D) ²⁰ : 1.4540) were obtained.

(xiv) Difluoromethylene-3,4-dioxybenzoic acid

100 ml of anhydrous hydrofluoric acid were initially introduced into thereaction vessel at -3° C. and 55 g of5-chlorocarbonyl-2,2-dichlorobenzodioxole were then added dropwise. Whenthe addition had ended, the mixture was warmed further to 20° C. andstirred until the evolution of hydrogen chloride had ended. The excesshydrofluoric acid was then distilled off and the residue was stirredinto 200 ml of 5% strength sodium hydroxide solution. The solution wasfiltered and then acidified with hydrochloric acid. Thedifluoromethylene-3,4-dioxybenzoic acid which had precipitated wasfiltered off and dried. 35 g of acid with a melting point of 153°-154°C. were obtained.

(xv) 2,2-Difluorobenzodioxole

(a) 600 g of anhydrous hydrofluoric acid were initially introduced intoa V₄ A reaction vessel with a stirrer, reflux condenser and droppingfunnel at -10° C. 612 g of 2,2-dichlorobenzodioxole were then addeddropwise in the course of about 2 hours, with exclusion of moisture.Evolution of hydrogen chloride started immediately. The gas was passedthrough a delivery tube from the reflux condenser into a receivercontaining water and was absorbed. When the addition had ended, thetemperature was increased to 18°-20° C. and the mixture was subsequentlystirred for a further 1 hour until the evolution of gas had ended. Theexcess hydrofluoric acid was now distilled off over a column andcollected in a cooled receiver. 394 g of 2,2-difluorobenzodioxole (n_(D)²⁰ : 1.4430) were then distilled over under a pressure of 100 mm with aboiling point of 65°-70° C. The yield was 78% of theory.

(b) A solution of 150 g of 2,2-dichlorobenzodioxole in 200 ml ofmethylene chloride was added dropwise to 200 ml of anhydroushydrofluoric acid in a V₄ A reaction vessel, while stirring. Thereaction started immediately at 0° C. The mixture was allowed to reactcompletely at 0° C., the temperature was then increased to 20° C. andthe mixture was stirred for a further hour. The excess hydrofluoric acidand the solvent were then distilled off under reduced pressure and the2,2-difluorobenzodioxole was subsequently distilled over. 85 g ofproduct were obtained, which corresponded to 68% of theory.

(xvi) 2,2-Difluoro-5-chloro-benzodioxole was obtained analogously toxv(a). Boiling point=57° C./14 mm Hg (n_(D) ²⁰ =1.4712),

(xvii) 2,2-Difluoro-1,4-benzodioxene

110 g of pyrocatechol were initially introduced into 300 ml oftetramethylene sulphone, together with 70 g of potassium hydroxide, andthe mixture was heated to 100° C. in the course of 30 minutes, whilestirring. 140 g of 1,1-difluoro-2-chloroethylene were passed in at atemperature of 110°-110° C. (time: about 3 hours). The product was thendistilled over a small column under 15 mm Hg into a well cooledreceiver. During this procedure, it was heated up to an internaltemperature of 100° C. The contents of the receiver were transferred toa separating funnel and the organic phase was separated off from theaqueous phase. 112 g (=65% of theory) of 2,2-difluoro-1,4-benzodioxenewhich had the refractive index n_(D) ²⁰ of 1.4802 and which, accordingto analysis by gas chromatography, was pure, were obtained.

(xviii) 6-Methyl-2,2,3-trifluoro-1,4-benzodioxene

124 g of 4-methylpyrocatechol were initially introduced into 300 ml oftetramethylene sulphone, together with 110 g of potassium hydroxide, at110° C. 170 g of trifluorochloroethylene were then passed in in thecourse of 4 hours. The mixture was then distilled over a column under 15mm Hg, the distillate being removed up to a transition temperature of85° C. After separating off the aqueous phase in the receiver, theproduct was again distilled. 133 g (=65% of theory) of6-methyl-2,2,3-trifluoro-1,4-benzodioxene were obtained at a boilingpoint 70°-72° C./12 mm Hg (n_(D) ²⁰ : 1.4565).

(xix) 2,2,3-Trifluoro-1,4-benzodioxene

220 g of pyrocatechol and 130 g of sodium hydroxide were initiallyintroduced into 600 ml of tetramethylene sulphone at 95°-105° C. and 330g of trifluorochloroethylene were passed in at this temperature, whilststirring. The mixture was then distilled over a column under 15 mm Hgand a fraction of boiling point 20° to 60° C./15 mm Hg was collected ina well-cooled receiver. After the H₂ O phase had been separated off, 332g of pure 2,2,3-trifluoro-1,4-benzodioxene of boiling point 54°-5° C./12mm Hg and n_(D) ²⁰ of 1.4525 remained, in a yield of 87% of theory.

(xx) 2,2,3-Trifluoro-5,7,8-trichloro-6-chloromethyl-1,4-benzodioxene

60 g of 6-methyl-2,2,3-trifluoro-benzodioxene were initially introducedinto the reaction vessel with 1 g Fe Cl₃ at 25° C. and chlorine waspassed into this mixture. The temperature was allowed to rise slowly to80° C. and chlorination was continued until saturation took place. Aftera short preliminary run 71 g of product with a melting point of 84°-86°C. were distilled at 120°-125° C./0.15 mm.

(xxi) 3-difluoromethoxy-2,4,5,6-tetrachloro-benzylchloride

100 g of difluoromethoxy-toluene were chlorinated with 2 g of iodine at25°-30° C. After passing in approximately 150 g of chlorine the reactionmixture solidified and 50 ml of CH₂ Cl₂ were added and chlorinationcontinued at 40° C. until saturation took place. After the solvent hadbeen distilled off a solid product remained which was introduced into afilter and subsequently washed with cyclohexane. 140 g of3-difluoromethoxy-tetrachlorotoluene were obtained (melting-point86°-88° C.). This was dissolved in 250 ml of o-dichlorobenzene andchlorinated with about 150 g of chlorine at 175°-185° C. underulta-violet irradiation. Following distillation (b.p.=140°-142° C./1.2mm) 112 g of 3-difluoromethoxy-2,4,5,6-tetrachlorobenzyl chloride wereobtained.

(xxii) 4,6,7-Trichloro-2,2-difluoro-5-chloromethylbenzodioxole

162 g of 5-methyl-2,2-difluoro-benzodioxole were initially introducedinto the reaction vessel with 1 g Fe S at 10° C. and chlorine was passedin. When the chlorine absorption decreased, the temperature wasincreased slowly until saturation was reached at 70° C. After apreliminary running 210 g of5-chloromethyltrichloro-2,2-difluorobenzodioxole of b.w.=104°-105°C./0.3 mm were obtained. Melting point 48°-50° C.

(xxiii) 3-trifluoromethoxy-benzyl alcohol was obtained by the reductionof 3-trifluoromethoxy-benzoylfluoride with NaBH₄ in dioxane B.p.=95°-97°C./15 mm: n_(D) ^(W) =1.4485. 3-chlorodifluoromethoxybenzyl alcohol:b.p.=123° C./14 mm: n_(D) ²⁰ =1.480 was obtained analogously from3-chlorodifluoromethoxy benzoylfluoride.

(xxiv) 2,2,3-trifluoro-6-hydroxy-cyano-methyl-1,4-benzodioxene

40 g of hexamethylene tetramine were heated in 50 ml water to 100° C.and 40 g of 6-chloromethyl-2,2,3-trifluorobenzodioxene were addeddropwise. After one hour at 100° C. 100 ml of H₂ O and 100 ml ofconcentrated hydrochloric acid were added and the mixture was stirredfor 2 hours at 100° C. By means of subsequent steam distillation 20 g of6-formyl-2,2,3-trifluoro-1,4-benzodioxene were obtained with ab.p.=119°-120° C./15 mm; n_(D) ²⁰ =1.5001), which was convertedanalogously to Example (iii) with KCN into cyanohydrin.

(xxv) 3-Trifluoromethoxy-benzoyl fluoride were initially introduced with5 g Fe S under reflux (167° C.) into the reaction vessel and chlorinewas passed in. The chlorine absorption was poor at the beginning, butincreased at the same rate as the temperature. At 180° C. chlorinationwas carried to saturation.

This raw mixture was reduced in 500 ml of dioxene at 20° C. with 65 g ofsodium boron hydride and extracted with CH₂ Cl₂ (following hydrolysis)and distilled. At b.p.₁₅ =148°-152° C. a fraction was obtained which,after standing at 20° C., partly crystallized. The crystals werefiltered off with suction and were washed with hexane, melting point50°-52° C.; according to H¹ NMR-spectrum5-trifluoromethoxy-2,3,4-trichlorobenzyl alcohol was obtained.

After distilling off the hexane an oil remained 80% of which, accordingto H¹ -NMR consisted of 3-trifluoromethoxy-2,5,6-trichlorobenzylalcohol.

The second fraction in the distillation (b.p.₁₃ : 170°-5° C., 76°-8° C.)consisted of 3-trifluoromethoxy-2,4,5,6-tetrachlorobenzyl alcohol.##STR43##

6.09 g (0.035 mol) of 2-difluoromethoxybenzyl alcohol and 3.5 g (0.035mol) of triethylamine were dissolved in 50 ml of toluene and thesolution was added dropwise to a mixture of 7.95 g (0.35 mol) of2,2-dimethyl-3-(2',2'-dichloro-vinyl)-cyclopropanecarboxylic acidchloride in 100 ml of toluene at 20°-25° C. The reaction mixture wassubsequently stirred at room temperature for 3 hours and poured into 150ml of water, the toluene phase was filtered off, washed with 100 ml ofwater and dried with sodium sulphate and the toluene was distilled offin vacuo. Last residues of solvent were removed by incipientdistillation at a bath temperature of 60° C./0.2 to 1.0 mm Hg. 10.9 g(81% of theory) of 2-difluoromethoxybenzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate wereobtained as a viscous oil with the refractive index n_(D) ²⁰ =1.5190.

The following compounds were obtained analogously:

    ______________________________________                                   Refractive    Com-                           index    pound Formula                  n.sub.D.sup.20    ______________________________________           ##STR44##               1.5191    3           ##STR45##               1.5070    4           ##STR46##               1.5260    5           ##STR47##               1.5240    6           ##STR48##               1.5230    7           ##STR49##               1.5170    8           ##STR50##               1.5154    9           ##STR51##               1.5062    ______________________________________

EXAMPLE 2 ##STR52##

6.81 g (0.03 mol) of 3-difluoromethoxy-benzyl bromide and 6.27 g (0.03mol) of 2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylic acidwere dissolved in 150 ml of toluene, 0.5 g of tetrabutylammonium bromideand 2 g of powdered KOH (industrial product, 87% pure) were added andthe mixture was heated to the boil for 2-3 hours. After cooling, thereaction mixture was poured into 150 ml of water, the toluene phase wasseparated off, washed with 100 ml of water and dried with sodiumsulphate and the toluene was distilled off in vacuo. Last residues ofsolvent were removed by incipient distillation at a bath temperature of60°-80° C./0.2 to 1 mm Hg. 8.3 g (78% of theory) of3-difluoromethoxy-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate wereobtained as a viscous oil with the refractive index n_(D) ²⁰ =1.5110.

EXAMPLE 3

The procedure followed was as in Example 2, but 5.74 g (0.03 mol) of3-difluoromethoxy-benzyl chloride were used instead of3-difluoromethoxybenzyl bromide. After boiling the mixture under refluxfor 4 hours, 7.9 g (74% of theory) of 3-difluoromethoxy-benzyl2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate wereobtained.

The following compounds were obtained analogously to Example 2 or 3:

    __________________________________________________________________________                                      Refractive    Compound          Formula                     index n.sub.D.sup.20    __________________________________________________________________________    12           ##STR53##                  1.5200    13           ##STR54##                  1.5210    14           ##STR55##                  1.4960    15           ##STR56##                  1.5110    16           ##STR57##                  1.5080    17           ##STR58##                  1.5280    18           ##STR59##                  1.5154    19           ##STR60##                  1.5150    20           ##STR61##                  1.5136    21           ##STR62##                  1.5205    22           ##STR63##                  1.4992    23           ##STR64##                  1.4780    24           ##STR65##                  1.4950    25           ##STR66##                  1.5164    26           ##STR67##                  1.5090    27           ##STR68##                  1.5149    28           ##STR69##                  1.5193    29           ##STR70##                  1,543    30           ##STR71##                  1,546    31           ##STR72##                  1.538    __________________________________________________________________________

The following additional compounds were obtained analogously to Example1:

    __________________________________________________________________________                                    Refractive    Compound          Formula                   Index n.sub.D.sup.20    __________________________________________________________________________    32           ##STR73##                1.493    33           ##STR74##                1.532    34           ##STR75##                1.530    35           ##STR76##                1.538    36           ##STR77##                1.512    37           ##STR78##                1.517    __________________________________________________________________________

The insecticidal activity of the compounds of this invention isillustrated by the following biotest Examples.

In these Examples, the compounds according to the present invention areeach identified by the number (given in brackets) of the correspondingpreparative Example, which will be found later in this specification.

EXAMPLE 4

LT₁₀₀ test for Diptera

Test insects: Musca domestica (resistant)

Number of test insects: 20

Solvent: Acetone

The active compound was dissolved in the solvent at a rate of 2 g perliter. The solution so obtained was diluted with further solvent to thedesired lower concentrations.

2.5 ml of the solution of active compound were pipetted into a Petridish. On the bottom of the Petri dish there was a filter paper with adiameter of about 9.5 cm. The Petri dish remained uncovered until thesolvent had completely evaporated. The amount of active compound persquare meter of filter paper varied with the concentration of thesolution of active compound. The stated number of test insects was thenplaced in the Petri dish and the dish was covered with a glass lid.

The condition of the test insects was continuously checked. The timewhich was necessary for a 100% knockdown effect was determined.

In this test, for example, the following compounds showed a superioraction compared to the prior art: (3), (4), (6), (15), (8), (10), (1),(12), (13) and (17).

EXAMPLE 5

LT₁₀₀ test for Diptera

Test insects: Aedes aegypti

Number of test insects: 20

Solvent: Acetone

The active compound was dissolved in the solvent at a rate of 2 g perliter. The solution so obtained was diluted with further solvent to thedesired lower concentrations.

2.5 ml of the solution of active compound were pipetted into a Petridish. On the bottom of the Petri dish there was a filter paper with adiameter of about 9.5 cm. The Petri dish remained uncovered until thesolvent had completely evaporated. The amount of active compound persquare meter of filter paper varied with the concentration of thesolution of active compound. The stated number of test insects was thenplaced in the Petri dish and the dish was covered with a glass lid.

The condition of the test insects was continously checked. The timewhich was necessary for a 100% knockdown effect was determined.

In this test, for example, the following compounds showed a superioraction compared to the prior art: (1), (3), (4), (6), (8), (10), (12),(13), (15), (17) and (2).

EXAMPLE 6

Mosquito larvae test

Test insects: Aedes aegypti larvae (4th stage)

Solvent: 99 parts by weight of acetone

Emulsifier: 1 part by weight of benzylhydroxydiphenyl polyglycol ether

To produce a suitable preparation, the active compound was dissolved, ata rate of 2 g per liter, in the solvent containing the amount ofemulsifier stated above. The solution thus obtained was diluted withwater to the desired lower concentrations.

The aqueous preparations of the active compounds were placed in glassvessels and about 25 mosquito larvae were then placed in each glassvessel.

After 24 hours, the degree of destruction was determined as apercentage.

In this test, for example, the following compounds showed a superioraction compared to the prior art: (3), (4), (6), (15), (8), (10), (1),(12), (13) and (17).

EXAMPLE 7

Laphygma test

Solvent: 3 parts by weight of dimethylformamide

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof the active compound was mixed with the stated amount of solvent andthe stated amount of emulsifier and the concentrate was diluted withwater to the desired concentration.

Cabbage leaves (Brassica oleracea) were treated by being dipped into thepreparation of active compound of the desired concentration and wereinfested with caterpillars of the owlet moth (Laphygma frugiperda), aslong as the leaves were still moist.

After the specified periods of time, the destruction in % wasdetermined.

In this test, for example, the following compounds showed a superioractivity compared to the prior art: (4), (8), (1), (10), (17), (13),(12), (3), (6) and (15).

It will be appreciated that the instant specification and examples areset forth by way of illustration and not limitation, and that variousmodifications and changes may be made without departing from the spiritand scope of the present invention.

What is claimed is:
 1. A compound of the formula ##STR79## in which R¹is a 2,2-difluoroethylenedioxy or 2,2,3-trifluoroethylenedioxy radical,andX is ##STR80##
 2. A compound according to claim 1, of the formula##STR81##
 3. A compound according to claim 1, of the formula ##STR82##